From 9136a39e6cf69e49803ac6123a4ac4431bc915a2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= <u.kleine-koenig@pengutronix.de>
Date: Wed, 10 Nov 2021 09:49:50 +0100
Subject: [PATCH] pwm: lpc18xx-sct: Simplify driver by not using pwm_[gs]et_chip_data()
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Git-commit: 9136a39e6cf69e49803ac6123a4ac4431bc915a2
Patch-mainline: v5.18-rc1
References: git-fixes
The per-channel data is available directly in the driver data struct. So
use it without making use of pwm_[gs]et_chip_data().
The relevant change introduced by this patch to lpc18xx_pwm_disable() at
the assembler level (for an arm lpc18xx_defconfig build) is:
push {r3, r4, r5, lr}
mov r4, r0
mov r0, r1
mov r5, r1
bl 0 <pwm_get_chip_data>
ldr r3, [r0, #0]
changes to
ldr r3, [r1, #8]
push {r4, lr}
add.w r3, r0, r3, lsl #2
ldr r3, [r3, #92] ; 0x5c
So this reduces stack usage, has an improved runtime behavior because of
better pipeline usage, doesn't branch to an external function and the
generated code is a bit smaller occupying less memory.
The codesize of lpc18xx_pwm_probe() is reduced by 32 bytes.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/pwm/pwm-lpc18xx-sct.c | 23 ++++++-----------------
1 file changed, 6 insertions(+), 17 deletions(-)
diff --git a/drivers/pwm/pwm-lpc18xx-sct.c b/drivers/pwm/pwm-lpc18xx-sct.c
index 6cf02554066c..b909096dba2f 100644
--- a/drivers/pwm/pwm-lpc18xx-sct.c
+++ b/drivers/pwm/pwm-lpc18xx-sct.c
@@ -166,7 +166,7 @@ static void lpc18xx_pwm_config_duty(struct pwm_chip *chip,
struct pwm_device *pwm, int duty_ns)
{
struct lpc18xx_pwm_chip *lpc18xx_pwm = to_lpc18xx_pwm_chip(chip);
- struct lpc18xx_pwm_data *lpc18xx_data = pwm_get_chip_data(pwm);
+ struct lpc18xx_pwm_data *lpc18xx_data = &lpc18xx_pwm->channeldata[pwm->hwpwm];
u64 val;
val = (u64)duty_ns * lpc18xx_pwm->clk_rate;
@@ -236,7 +236,7 @@ static int lpc18xx_pwm_set_polarity(struct pwm_chip *chip,
static int lpc18xx_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
{
struct lpc18xx_pwm_chip *lpc18xx_pwm = to_lpc18xx_pwm_chip(chip);
- struct lpc18xx_pwm_data *lpc18xx_data = pwm_get_chip_data(pwm);
+ struct lpc18xx_pwm_data *lpc18xx_data = &lpc18xx_pwm->channeldata[pwm->hwpwm];
enum lpc18xx_pwm_res_action res_action;
unsigned int set_event, clear_event;
@@ -271,7 +271,7 @@ static int lpc18xx_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
static void lpc18xx_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
{
struct lpc18xx_pwm_chip *lpc18xx_pwm = to_lpc18xx_pwm_chip(chip);
- struct lpc18xx_pwm_data *lpc18xx_data = pwm_get_chip_data(pwm);
+ struct lpc18xx_pwm_data *lpc18xx_data = &lpc18xx_pwm->channeldata[pwm->hwpwm];
lpc18xx_pwm_writel(lpc18xx_pwm,
LPC18XX_PWM_EVCTRL(lpc18xx_data->duty_event), 0);
@@ -282,7 +282,7 @@ static void lpc18xx_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
static int lpc18xx_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
{
struct lpc18xx_pwm_chip *lpc18xx_pwm = to_lpc18xx_pwm_chip(chip);
- struct lpc18xx_pwm_data *lpc18xx_data = pwm_get_chip_data(pwm);
+ struct lpc18xx_pwm_data *lpc18xx_data = &lpc18xx_pwm->channeldata[pwm->hwpwm];
unsigned long event;
event = find_first_zero_bit(&lpc18xx_pwm->event_map,
@@ -303,7 +303,7 @@ static int lpc18xx_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
static void lpc18xx_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
{
struct lpc18xx_pwm_chip *lpc18xx_pwm = to_lpc18xx_pwm_chip(chip);
- struct lpc18xx_pwm_data *lpc18xx_data = pwm_get_chip_data(pwm);
+ struct lpc18xx_pwm_data *lpc18xx_data = &lpc18xx_pwm->channeldata[pwm->hwpwm];
clear_bit(lpc18xx_data->duty_event, &lpc18xx_pwm->event_map);
}
@@ -327,8 +327,7 @@ MODULE_DEVICE_TABLE(of, lpc18xx_pwm_of_match);
static int lpc18xx_pwm_probe(struct platform_device *pdev)
{
struct lpc18xx_pwm_chip *lpc18xx_pwm;
- struct pwm_device *pwm;
- int ret, i;
+ int ret;
u64 val;
lpc18xx_pwm = devm_kzalloc(&pdev->dev, sizeof(*lpc18xx_pwm),
@@ -398,16 +397,6 @@ static int lpc18xx_pwm_probe(struct platform_device *pdev)
lpc18xx_pwm_writel(lpc18xx_pwm, LPC18XX_PWM_LIMIT,
BIT(lpc18xx_pwm->period_event));
- for (i = 0; i < lpc18xx_pwm->chip.npwm; i++) {
- struct lpc18xx_pwm_data *data;
-
- pwm = &lpc18xx_pwm->chip.pwms[i];
-
- data = &lpc18xx_pwm->channeldata[i];
-
- pwm_set_chip_data(pwm, data);
- }
-
val = lpc18xx_pwm_readl(lpc18xx_pwm, LPC18XX_PWM_CTRL);
val &= ~LPC18XX_PWM_BIDIR;
val &= ~LPC18XX_PWM_CTRL_HALT;
--
2.35.3